/* socketpair.c
 * Copyright 2007 by Nathan C. Myers <ncm@cantrip.org>; some rights reserved.
 * This code is Free Software.  It may be copied freely, in original or 
 * modified form, subject only to the restrictions that (1) the author is
 * relieved from all responsibilities for any use for any purpose, and (2)
 * this copyright notice must be retained, unchanged, in its entirety.  If
 * for any reason the author might be held responsible for any consequences
 * of copying or use, license is withheld.  
 */

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#include "SocketPair.h"

// stl
#include <string.h>

// Win32
#include <Winsock2.h>
#include <WS2tcpip.h>

int socketpair(int d, int type, int protocol, int sv[2])
{
    union {
       struct sockaddr_in inaddr;
       struct sockaddr addr;
    } a;
    SOCKET listener;
    int e;
    socklen_t addrlen = sizeof(a.inaddr);
    DWORD flags = 0;
    int reuse = 1;

    if (sv == 0) {
      WSASetLastError(WSAEINVAL);
      return SOCKET_ERROR;
    }

    listener = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (listener == INVALID_SOCKET) 
        return SOCKET_ERROR;

    memset(&a, 0, sizeof(a));
    a.inaddr.sin_family = AF_INET;
    a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
    a.inaddr.sin_port = 0; 

    sv[0] = sv[1] = INVALID_SOCKET;
    do {
        if (setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, 
               (char*) &reuse, (socklen_t) sizeof(reuse)) == -1)
            break;
        if  (bind(listener, &a.addr, sizeof(a.inaddr)) == SOCKET_ERROR)
            break;
        if  (getsockname(listener, &a.addr, &addrlen) == SOCKET_ERROR)
            break;
        if (listen(listener, 1) == SOCKET_ERROR)
            break;
        sv[0] = WSASocket(AF_INET, SOCK_STREAM, 0, NULL, 0, flags);
        if (sv[0] == INVALID_SOCKET)
            break;
        if (connect(sv[0], &a.addr, sizeof(a.inaddr)) == SOCKET_ERROR)
            break;
        sv[1] = accept(listener, NULL, NULL);
        if (sv[1] == INVALID_SOCKET)
            break;

        closesocket(listener);
        return 0;

    } while (0);

    e = WSAGetLastError();
    closesocket(listener);
    closesocket(sv[0]);
    closesocket(sv[1]);
    WSASetLastError(e);
    return SOCKET_ERROR;
}
